Nat Rothschild charged Bumi more than £4m for the use of his private jet “N4T”
during an 18-month period that took in flights everywhere from the world’s
biggest cities to far-flung Mauritania.

Documents seen by The Daily Telegraph show that the financier invoiced the bombed-out coal miner for £4.36m between July 2010 and December 2011 for flights on his Gulfstream jet.

The invoices, in euros, include €286,137 (£237,400) for travel between Paris, Doha, Singapore, Vienna and Luton in November 2010 for meetings relating to the creation of Bumi – the group he formed via a fateful $3bn (£1.87bn) deal with Indonesia’s Bakrie family.

Mr Rothschild also put in a €360,569 invoice for a six-day site visit and analyst meeting that took in stops in Jakarta and Beijing in December 2010, where the six passengers included Bumi’s former finance director Andy Beckham.

He also invoiced €255,417 for a trip to Nouakchott, Mauritania, in March 2011 that also involved stops in Vienna, Hong Kong and Tel Aviv and €114,832 for a journey described as “Bakrie meeting in Dubai @ airport” in May 2011, which started from Bordeaux.

There is no suggestion that the flights were not authorised by the Bumi board, whose senior independent director Sir Julian Horn-Smith also used Mr Rothschild’s jet. Sir Julian was the sole passenger when he travelled between London and Berlin for a board meeting in June 2011. The invoice for that was €62,146.

Mr Rothschild’s private jet has become the latest bone of contention between the financier and the board in the bitter row over control of Bumi. It was brought to a head last week by the decision of Mr Rothschild, who controls 18.2pc of the votes, to call for an EGM in an attempt to oust 12 of 14 directors.

Sources close to Mr Rothschild insist that the flight expenses were not only approved by the board but should be offset against his decision to waive £10m of adviser fees for bringing the Bumi transaction to the company. “That saved the company £7m,” said one.

Lord Renwick, the non-executive director who chairs Bumi’s audit committee, said the board approved Mr Rothschild’s use of the jet at the outset when he employed it to raise funds for his Vallar cash shell – the financial vehicle he used to acquire Bumi.

“He took the lead in helping to raise $1bn at Vallar and, to be fair to Nat, he devoted enormous energy to that,” Lord Renwick said. “It was argued by the audit committee that, as Nat had to race around the world, he could use the private jet for that purpose. However, later it became a lifestyle choice. He was using it when it was not operationally necessary.”

Mr Rothschild claimed €316,701 for a three-day trip in September 2011 to meet Nirwan and Indra Bakrie that involved flights from London to Baku, Jakarta, Tokyo and Newark. The only other passenger was Tom Daniel, one of the Vallar advisers. Mr Rothschild also put in a €79,792 invoice for return flights from Paris for a meeting at London’s 4 Grosvenor Place in October 2011.

The financier, who quit the board in October to fight for minority shareholders, flew to Mauritania to try to establish what had happened to funds that had disappeared from one of Bumi’s associate companies.

Nick von Schirnding, Bumi’s new chief executive, said he had ended any use of private jets at Bumi. “Driving down costs is my number one priority,” he said. “First class travel and private jets have no role in the organisation I am running.”

To set an example “from the top”, he said, he had “started an urgent review of head office costs and we will be getting out of our head office in Knightsbridge, which is totally inappropriate”.